Clinical significance and prognostic value of serum RCAS1 in patients with non-small cell lung cancer.

Receptor-binding cancer antigen expressed on SiSo cells (RCAS1) is a human tumor-associated antigen that induces cell-cycle arrest and apoptosis in cells. The aim of this study was to explore the clinical significance and prognostic value of serum RCAS1 levels in patients with non-small cell lung cancer (NSCLC). Serum specimens from 97 patients with NSCLC, 30 healthy volunteers (HVs) and 60 patients with benign lung diseases (BLD) were collected. The concentrations of RCAS1 were measured by enzyme-linked immunosorbent assay (ELISA). Serum RCAS1 levels were higher in the NSCLC group in comparison with the HV and BLD groups (p<0.001). With a cutoff point of 19.8 U/mL, RCAS1 showed a good diagnostic performance for NSCLC. Univariate analysis revealed that NSCLC patients with elevated RCAS1 levels had significantly shorter overall survival times (p=0.013). By multivariate analysis, serum RCAS1 was identified as an independent prognostic factor (p=0.003). Measurement of RCAS1 might be a useful diagnostic and prognostic marker in NSCLC.